Updated

A man considered a "person of interest" in a string of 10 killings in seven states has been charged with raping a woman who was found off a highway in northern Oklahoma.

Carl W. Lawson (search), 32, of Lincoln, Neb., was charged last week with rape, kidnapping, and assault and battery with intent to kill. Copies of the charges and supporting documents were released by the Oklahoma County District Attorney's office on Tuesday.

Investigators are awaiting results of tests to see if Lawson's DNA matches the killer in the string of homicides, said Debra Forshee, a spokeswoman for the Oklahoma County district attorney.

The victims were found in or disappeared from Oklahoma, Pennsylvania, Indiana, Mississippi, Texas, Arkansas and Tennessee. Many were truck-stop prostitutes.

Efforts will be made to extradite Lawson from Lincoln, where he was arrested Tuesday on the Oklahoma warrant, Forshee said.

He is accused of picking up a 51-year-old woman at an Oklahoma City truck stop Sept. 12 and beating, choking and raping her before dumping her near Interstate 35, near the Oklahoma-Kansas line. The woman was found by a motorist after regaining consciousness.

Investigators retrieved a bloody fast-food bag near where she was found, and in it were trucking logs from the company that employed Lawson. The alleged victim also picked Lawson's photograph from a lineup.

According to court papers, the woman told police that during her ordeal the suspect said, "The first three, four I killed it bothered me, but I kind of like it now."

Lawson allegedly told authorities he had smoked crack with a woman at the truck stop, they got into an argument over money she stole from him and he hit her, cutting her eye.

Investigators found similarities between the rape and the series of homicides, said Jessica Brown, a spokeswoman for the Oklahoma State Bureau of Investigation (search).

Many of the victims were picked up at truck stops, strangled and left by the side of the road. Some of the women were found partly clothed, others were naked.

Investigators are tracing Lawson's movements over the past year. "It could be some time before we have any answers to our questions," Brown said. "He remains a person of interest at this time."